Study On The Influence Of Properties Of Components On The Piezoelectricity Of 0-3 Composites

0-3 piezo-composites comprise ceramic powder and three-dimensional polymer. They exhibit many advantates, such as low brittleness, low density and low permittivity. But the low piezoelectricity of composites limits its application. In order to improve piezoelectric properties, the ceramics and the third component of composites were studied.The theoretical Dilute model was set up, and the properties of composites were analyzed. According to this model, some factors that affect the composites' properties were found out, such as the size, permittivity, and piezoelectricity of ceramic powder.The permittivity of the components affects the distribution of electric field directly. In composites, the components of low permittivity could produce high electric field. A valid way to enhance electric field in ceramic particles is to reduce the permittivity of ceramic or to improve that of polymer matrix. The permittivity of ceramics could be reduced by doping some ingredients. However, because of the low permittivity of polymers, the third dopant was added . Finally, the composites with high piezoelectric constant were obtained.The shape of ceramic powder is another important factor that influences piezoelectric constant of composites. Simply reducing the particle size of ceramic powder is useless to increase piezoelectricity. Through mixing different sizes of powder uniformly, smaller particles could fill in the interspace formed by bigger particles. This will improve the piezoelectricity of 0-3 composites and the maximal content of ceramic.In this paper, piezoelectric ceramics with low permittivity and 0-3 composites were prepared, meanwhile the process were determined. Poly-aniline was prepared and added into composites as the third dopant. At last the composites were polarized at a certain temperature and electric field. The property test shows that the piezoelectricity of composites is enhanced by utilizing ceramic powders with low permittivity and good size distribution and proper addition of Poly-aniline.